Another factor, of course, is the increasingly small share of the overall CMBS that's represented by delinquent loans. Morningstar said last month that as of this past November, delinquencies from deals issued from 2005 through 2008 represented 87.2% of all delinquencies by balance, although legacy CMBS comprised less than 6% of the overall CMBS pie. Comparatively, delinquencies from deals issued from 2013 through 2017 contribute 11.2% of all delinquencies and represent 0.3% of the CMBS universe.

Annual private-label CMBS issuance in the years since the downturn has yet to crack the $100-billion barrier, let alone scale the heights reached in 2007, when $230.5 billion of deals were securitized. However, the third quarter of '17 saw the CMBS sector reverse a decade-long downward trend and increase its holdings by 0.8%, according to the Mortgage Bankers Association. Issuance was generally expected to finish '17 at between $85 billion and $90 billion.

The forecast for the coming year varies depending on the source. As part of its 2018 MBA CREF Outlook Survey released earlier this month, MBA said the expectation was generally for CMBS issuance to remain flat or increase, with 23% of respondents predicting increases averaging less than 5%.

For their part, ratings agencies expect issuance this year to be either flat or show a slight decline, given factors that include a considerably lower volume of maturing CMBS loans to refinance. Fitch and Kroll Bond Rating Agency both expect single-borrower activity to be strong this year, but predict that non-agency issuance overall will decline. Fitch expects a drop to $75 billion, while KBRA sees private-label volume of about $65 billion. Morningstar predicts volume between $70 billion and $75 billion, while S&P Global Ratings is somewhat more optimistic, expecting only a slight drop from '17 levels.